Process for breaking petroleum emulsions



PatentedMan' 1944 STATES ATENT oFFlcE.

PROCESS FOR BREAKING PETROLEUM EMULSIONS Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., assignors to Petrolltc Corporation, Ltd, Wilmington, Del., a corporation of Delaware No Drawing. Application June 15, 1942, Serial No. 447,151

'8 Claims.

This invention relates primarily to the resolution of petroleum emulsions.

The main object of our invention is to provide a novel process for resolving petroleum emulsions of the water-in-oil type, that are commonly re-- ferred to as "cut oil, "roiiy oil, emulsified relatively soft waters or weak brines. Controlled emulslfication and subsequent demulsiflcation under the conditions just mentioned is of significant value in removing impurities, particularly inorganic salts, from pipeline oil.

We have discovered that if one oxyalkylates glycerol so as to introduce at least three oxyalkylene radicals for each hydroxyl group, and if the product so obtained is reacted with a polybasic carboxy acid having not over eight carbon atoms, and in such a manner as to yield a fractional ester, due to the presence of at least one free carboxyl radical, one can then esterify said acidic material or intermediate product with at least one mole of an alcoholic compound of the type herein described to give a variety of new compositions of matter which are emcientdemulsifiers for crude oil emulsions.

The compounds used as the demulsifler in our herein described process may be produced in any suitable manner, but are usually manufactured ,by following one of two general procedures. In

one of said procedures oxyalkylated glycerol, which is, in essence, a polyhydric alcohol, is reacted with a polybasic acid so as to give an acidic material, or intermediate product,.which, in turn, is reacted with an alcoholic body of the kind hereinafter described, and momentarily indicated by the formula Rl*(OH)m. Generically,

the alcoholic body herein contemplated may be 4 considered a member of the class in which 121, may vary from 1 to 10, although the specific significance of m in the present instance will be hereinafter indicated. The second procedure is to react an alcohol of the formula type (Cl. 252-340) V Rl(OH)m with'a polybasic acid, so as to produce an intermediate product, and then react said intermediate product or fractional ester with the selected o'xyalkylated glycerol. Glycerol may be conveniently indicatedby "the following formula:

If treated with an oxyalkylating agentnind momentarily consideration will be limited to an oxyethylating agent, one may obtain an oxyethylated glycerol of the following formula:

15 cmiown CsHaOa-(CzHaOh H (CzHnO),vH in which the value of 11. may vary from 3 to 10 and all the values'of n need not be identical.

If a polybasiccarboxy acid be indicated by the formula: I

coon

" Rcoon coon then the acyclic reaction product of one mole of oxyethylated glycerol and one mole of a polybasic carboxy acid may be indicated by the following formula:

cimo ooca(coon ,.-i enact-(0,1140) an (CzHi0)-'H then the compound may be indicated by the following formula:

60 (GiHiOLuOOCINCOOHL- cimoi-(clmmnloocmcoonm (CHi0),,'H Likewise, if three moles of a polybasic acid ar 5 employed, the compound may be indicated by the following formula:

omimnoocawoon) c,H,o,- c,Hlo)..-oocawoomw fun tionality.

If a fractional ester of the kind exemplified by the three preceding formulas is reacted with one or more moles of an alcohol of the kind previously described in a generic sense as R1(OH)m' then obviously, one may obtain a material of the type indicated by the following formula:

(00011 [(cnnonoocr/ (coonm' z whichmiso,1or2,yis0,1or2,and i; 1, 2 or 3, and a." is 0, or 1, and y is 1 boxylic hydrogen atom appears, it may be re-v placed by metal, an ammonium radical, or substituted ammonium radical, or by an organic group derived from an alcohol, such as an aliphatic alcohol, an aralkyl alcohol, or an aiicyclic alcohol. It may also be converted into an amide, including a polyaminoamide. Thus, the preceding formula may be rewritten in its broader scope, as follows:

[(G.H:.0)..'0ocnw zlwh in which n replaces the numbers 2, 3 or 4, z includes the acidic hydrogen atom itself. In the above formula, and hereafter, for convenience, R1 is intended to include any hydroXyl groups that remain.

If the compounds herein contemplated are obtained under usual conditions, at the lowest temperatures, then the monomeric form is most likely to result. The production of the compounds herein contemplated is the result ofone or more esteriflcation steps. As is well known, esterification procedures can be carried out in various manners, but generally speaking, esterifications can be carried out at the lowest feasible temperatures by using one or several procedures. One procedure is to pass an inert, dried gas through the mass to be esterifled, and have present at the same time a small amount of awatalyst, such as dried HCl gas, a dried sulfonic acid, or the like. Another and better procedure, in many instances, is to employ the vapors of a suitable liquid, so as to remove any water formed and condense both the vapors of the liquid employed and the water in such a manner as to trap out the water and return the liquid .6 the reacting vessel. This procedure is commonly employed in the arts, and for convenience, reference is made .to U. S. Patent No. 2,264,759, dated Dec. 20, 1941, to Paul C. Jones.

Referring again to the last two formulas indicating the compounds under consideration, it can be readily understood that such compounds, in

numerous instances, have the property of poly- In view of this-fact, where there is at least one residual carboxyl and at least one residual hydroxyl, one would expect that under suitable conditions, instead of obtaining the monomeric compounds indicated, one would, in reality, obtain a polymer in the sense, for example, that polyethylene glycols represent a polymer of ethylene glycol. The term polymer" is frequently used to indicate the polymerized product derived from a monomer in which the polymer has the same identical compositionas the monomer. In the present instance, however, polymerization involves the splitting and loss of water so that the process is essentially selfesteriflcation. Thus, strictly speaking, the polymeric compounds are not absolutely isomers of the monomeric compounds, but since, for all practical purposes, they can be so indicated, and

'since such practice is common in the arts concerned with materials of this type, it is so adopted here. Thus, reference in the appended claims to polymers is intended to include the self-esteriiication products of the monomeric compounds.

In view of what has been said, and in view of the recognized hydrophile properties of the recurring oxyalkylene linkages, particularly the oxyethylene linkage, it is apparent that the materials herein contemplated may vary from compounds which are clearly water-soluble'through self-emulsifying oils, to materials -which are balsam-like and sub-resinous or semi-resinous in nature. The compounds may vary from monomers to polymers, in which the, unitary structure appears a number of times, for instance, 10.0r 12 times. It is to be noted that true resins, i. e., truly insoluble materials of a hard plastic nature, are not herein included. In other words, the polymerized compounds are soluble to a fairly definite extent, for instance, at least 5% in some solvents, such as water, alcohol, benzene, dichloroethyl ether, acetone, cresylic acid, acetic acid, ethyl acetate, dioxane or the like. This is simply another way of stating that the polymerized product contemplated must be of the sub-resinous t p which is commonly referred to as an A resin, or a B resin, as distinguished from a C resin, which is a highly infusible, insoluble resin (see Ellis, Chemistry of Synthetic Resins (1935), pages 862, et seq.).

Reviewing the form as presented, it is obvious group, the carboxylic hydrogen atom may, of

course, be replaced by any ionlzable hydrogen atom equivalent, such, for example,. as a metal, an ammonium radical, a substituted ammonium radical, etc. In the hereto appended claims the word polar is used in this specific sense.

We are aware that compounds similar to those contemplated in the present instance may be derived from polyhydroxylated compounds having more than three hydroxyl groups. For instance, they may be derived from acyclic diglycerol, triglycerol, tetraglycerol, mixed polyglycerols, mannitol, sorbitol, various hexitols, dulcitol, pentaerythritol, sorbitan, mannitan, dipentaerythritol monoether, and other similar compounds. Such particular types in which higher pyrolysis.

hydroxylated materials are subjected to oxyalkylation and then mployed in the same manner as oxyalkylated glycerol is employed in the,

compounds which jiiay be used as reactants to replace oxyalkylated glycerol, or oxyalkylated ethylene glycol, which latter reactant is described in a co-pending application hereinafter referred to. The reactants thus contemplated include the 'type in which there is an amino or amido nitrogen atom, particularly, when present in a low molal type of compound prior to oxyalkylation, reference being made to polyhydroxylated materials, including those having two or three hydroxyl groups, as well as those having more than three hydroxyl groups. For instance, the oxyalkylated derivatives, particularly the oxyethylated derivatives of ethyldiethanolamine, bis(hydroxyethyllacetamide, the acetamide of tris (hydroxymethyl) aminomethane, tetrahydroxyl- 'ated'ethylene diamine, etc. Compounds may also be derived from cyclic diglycerol and the like.

Furthermore, for convenience, attention is directed to a somewhat similar class of materials which are described in U. S. Patent No. 295,164, dated September 8, 1942, to DeGroote and Keiser. Said patent involves the use of the same type of alcoholic bodies for reactants, but is limited,

among other things, to the-compounds which are essentially symmetrical in nature, for instance, involving the introduction of two alcoholic residues, whereas, in the present instance, one, two, or three, or more, might be introduced.

As indicated previously, the polybasic acids employed are limited to the type having not more than eight carbon atoms, for example, oxalic, malonic, succinic, glutaric, adipic, maleic, and phthalic. Similarly, one may employ acids such as fumaric, glutaconic, and various others, such as citric, malic, tartaric, and the like. The selection of the particular tribasic or dibasic acid employed, is usually concerned largely with the convenience of manufacture of the finished ester, and also the price of the reactants. Generally speaking, phthalic acid or anhydride tends to produce resinous materials, and greater care must be employed if the ultimate or final product be of a subresinous type. Specifically, the preferred type of polybasic acid is such as to contain six carbon atoms or less. Generally speaking, the higher the temperature employed, the easier'it is to obtain large yields of esterified product, al-

though polymerization may be stimulated. Oxalic acid may be comparatively cheap, but it decomposes readily at slightly above the boiling point of water. For this reason it is more desirable to use an acid 'which is more resistant to Similarly, when a polybasic acid is available in the form of an anhydride, such anhydride is apt to produce the ester with greater case than the acid itself. For this reason, maleic anhydride is particularly adaptable, and also, everything else considered, the cost is comparatively low on a per molar basis, even though somewhat higher on a per pound basis. Succinic acid or the anhydride has many attractive qualities of maleic anhydride, and this is also true of adipic acid. For purposes of brevity, the bulk of the examples hereinafter illustrated will refer to the use of maleic anhydride, although it is understood that any other suitable polybasic acid may bevemployed. Furthermore, reference is made to derivatives obtained by oxyethylatlon, although, as previously pointed out, other oxyalkylating agents may beemployed. I

As far as the range of oxyethylated glycerols employed as reactants is concerned, it is our preference to employ those in which approximately to 24 oxyethylene groups have been introduced 1 into a single glycerol molecule. This means that its approximately five to eight oxyethylene radicals have been introduced for each original hydroxyl group. I

The oxyalkylation of glycerol is a well known procedure ,(see Example 11 of German Patent No. 605,973, dated Nov. 22, 1934, to I. G. Farbenindustrie A. G.) The procedure indicated in the following three examples is substantially identical with that outlined in saidaiorementioned German patent.

OXYETHYLATED GLYCERQL Example 1 184 pounds of glycerol is mixed with V2%. y weight, of caustic soda solution having a specific gravity of 1.383. The caustic soda acts as a catalyst. The ethylene oxide is added in relatively small amounts, for instance, about 44 pounds at a time. The temperature employed is from -180 C. Generally speaking, the gauge pressure during the operation approximates 200 pounds at the maximum, and when reaction is complete, drops to zero, due to complete absorption of the ethylene oxide. When all the ethylene oxide has been absorbed and the reactants cooled, at second small portion, for instance, 44 more pounds of ethylene oxide, are added and the procedure repeated until the desired ratio of 15,

pound moles of ethylene oxide to one pound mole of glycerol is obtained. This represents 660 pounds of ethylene oxide for 92 pounds of glycerol.

Qxxa'rnrm'ren GLYCEROL Example 2 The ratio of ethylene oxide is increased to 18 pound moles for each pound mole of glycerol. Otherwise, the same procedure is followed as in Example 1, preceding.

OXYETHYLATED GLYCEROL Example 3 The same procedure is followed as in the two previous examples, except that the ratio of ethylene oxide to glycerol is increased to 21 to one.

OXYETHYLATED GLYCEROL Mama-rs Example 1 OXYETHYLATED GLYCEROL Marmara Example 2 The same procedure is followed as in the preceding example, except that two pound moles of maleic anhydride are employed so as to obtain the dimaleate instead of the monomaleate.

OXYETHYLA'IED GLYCEROL MALEATE Example 3 The same procedure is followed as in the two preceding examples, except that three pound moles of maleic anhydride are employed so as to obtain the trimaleate.

OXYETHYLATED GLYCEROL MALEATE Example 4 OXYE'IHYLATED GLYCEROL MALEATE Example 5 The same procedure is employed as in the preceding examples, except that oxyethylated glycerol (ratio 1 to 21) is employed instead of oxyethylated glycerol (ratio 1 to or (-1 to 18).

Previous reference has been made toan alcoholic body which has been defined generically by the formula R1(OH) m. The sub-generic class of alcoholic compounds employed as reactants in the manufacture of the present compounds, are materials commonly referred to as high molal alcohol acids, or high molal hydroxy acids. They are invariably water-insoluble. The commonest example is ricinoleic acid. Other hydroxy fatty acids include hydroxystearic acid, dihydroxystearic acid, diricinoleic acid, aleuritic acid, and the like. Similar acids are obtained in the oxidation of paraiiin, petroleum hydrocarbon, or wax, and are commonly referred to as hydroxylated wax acids. Hydroxylated wax acids occur as by-products in the oxidation of waxes or similar materials, and are usually separated so that the commonest commercial form of oxidized wax acids represent mixtures comparatively free from the hydroxylated compounds. Hydroxylated acids are produced by other procedures, such as chlorination, either by addition or substitution, as, for example, chlorination of oleic acid or stearic acid. Subsequent reactions involve the removal of the chlorine with the introduction of a hydroxyl radical. Undecylenic acid, derived from castor oil, has been converted into a hydroxy undecencic acid. Unsaturated hydroxy acids, such as ricinoleic acid, may be treated in various manners, so as to produc derivatives, for example, chlorinated or brominated ricinoleic acid. Such materials are entirely satisfactory for use as reactants in the preparation of materials of the kind herein contemplated. Naturallyoccurring naphthenic acids can also be converted into hydroxylated products by following similar procedure. An unsaturated hydroxy acid, such as ricinoleic acid, canbe converted into a hydroxylated arylstearic acid. Such procedure contemplates reactions such as those involving ricinoleic acid, benzene, and aluminum chloride in large excess, or involves the desulfonation of a sulfo-aromatic fatty acid. In any event, by employing derivatives of undecylenic acid, or one a a difficulty.

In some instances, derivatives of hydroxylated unsaturated acids are most readily obtained by the employment of an intermediate in which the hydroxy group is protected. Thus, ricinoleic acid may be acetylated, and such acetyl ricinoleic acid converted into a derivative, for instance, a derivative in which an aryl group is introduced. Such derivative can then be saponified or hydrolyzed so as to regenerate the hydroxyl radical.

COMPLETED MONOMERIC DERIVATIVE Example 1 One pound mole of a product of the kind described under the heading Oxyethylated glycerol maleate, Example 1 is reacted with one pound inole of ricinoleic acid, preferably in the absence of any high boiling hydrocarbon or inert solvent. However, if an inert vaporizing solvent is employed, it is generally necessary to use one which has a higher boiling range than xylene, and sometimes removal of such solvent might present In other instances, however, such high boiling inert vaporizing solvent, if employed, might be permitted to remain in the reacted mass and appear as a constituent or ingredient of the final product. In any event, our preference is to conduct the reaction in the absence of any such solvent and permit the reaction to proceed with the elimination of water.

The temperature of reaction is about to 200 C. and time of reaction about 20 hours.

COMPLETED MONOMERIC DERIVATIVE Example 2 The same. procedure is followed as in Completed' monomeric derivative, Example 1, preceding, except that the dimaleate described under the heading Oxyethylated glycerol maleate, Example 2 is used instead of the monomaleate.

COMPLETED MONOMERIC DERIVATIVE Example 3 The same procedure is followed as in the two preceding examples, except that the trimaleate is substituted for the monomaleate or dimaleate in the two preceding examples.

COMPLETED MONOHERIC DERIVATIVE Example 4 The same procedure is followed as in Examples Comrsrsn. MONOMERIO Dams-riva- Ezample The same procedure is followed as in Example 3, preceding, except that for each pound mole of trimaleate, instead of adding one pound mole of ricinoleic acid, oneadds three pound moles of ricinoleic acid. for reaction.

Courrrrm MONOMEBIG Driuwmvs Example 8 Reference: to. the. preceding examples will show that in each and every instance oxyethylated glycerol ratio 1 to has been employed as a raw material or primary reactant. In the present instance, a more highly oxyetlrylated glycerol is employed, to wit one involving the ratio of l to 18. (SeeOxyethylated glycerol maleate, Example 4,. preceding.) I

Comrr'rsn MONOMERIG DERIVATIVE Example 7 reactants. The products are mixed .and stirred 3 constantly during the heating and esteriflcation step. If desired, an inert gas, such as dried nitrogen or dried carbon dioxide, may be passed through the mixture. Sometimes it is desirable to add an esterification catalyst, such as suliuric acid, benzene sulionic acid, or the-like.

This is the same general procedure as employed in the manufacture of ethylene glycol dihydrogen dlphthalate. (See U. 8. Patent No. 2,075,107, dated March 30, 1937, to Frasier.)

Sometimes esterification is conducted most readily in the presence of an inert solvent, that carries away the water of esterification which may be formed, although as is readily appreciated,

such water of esteriflcation is absent when such type of reaction involves an acid anhydride, such as maleic anhydride, and a glycol. However, if water is formed, for instance, when citric acid is employed, then a solvent such as xylene may be present and employed to carry oi the water formed. The mixture of xylene vapors and water vapors can be condensed so that the water is separated. The xylene is then returned to the reaction vessel for further circulation. This is a conventional and well-known procedure and requires no further elaboration.

In the previous monomeric examples there is a definite tendency, in spite of precautions, at least in a number of instances, to obtain polymeric materials and certain cogeneric by-products. This is typical, of course, of organic 'reactions of this kind, and as is wellknown, organic reactions per se are characterized by the fact that 100% yields are the exception, rather than the rule, and that significant yields'are satisfactory, especially in those instances where the by-products or cogeners may satisfactorily serve with the same purposes as the principal or intentional product. This is true in the present instance. In many cases one is better off to obtain a polymer in thesense previously described,particularly a polymer whose molecular weight is a rather small multiple of the molecular weight of the monomer. For instance, a polymer whose molecular .weight is two, three, four, five, or six times the molecular weight of the monomer. Polymerization is hastened by the presence of an alkali, and thus in instances where it is necessary to have a maximum yield of the monomer, it may be necessary to take precautions that the alkali used in promoting oxyethyl'ation of glycerol, be removed before subsequent reaction. This, of course, can be done in any simple manner by conversion to sodium chloride, sodium sulfate, or any suitable procedure.

Previous reference has been made to the'iact that the carboxylic hydrogen atom might be variously replaced, by substituents, including organic radicals, for instance, the radicals obtained from alcohols, hydroxylated amines, nonhydroxylated amines, polyhydric alcohols,etc. Obviously, the reverse is also true, in that a free hydroxyl group may be esterified with a selected acid,.varying from such materials as riclnoleic acid to oleic acid, including alcohol acids, such'as hydroxyacetic acid, lactic acid, rlcinoleic acid and also polybasic acids of the kind herein contemplated.

With the above facts in mind, it becomes obvious that what has been previously said as to polymerization,v with the suggestion that byproducts or cogeneric materials were formed, may be recapitulated with greater definiteness, and one can readily appreciate that the formation of heat-rearranged derivatives or compounds must take place to a greater or'lesser degree. Thus, the products herein contemplated may be characterized by being monomers of the type previously described, oresterification polymers, or heat-rearranged derivatives of the same, and thus including the heat-rearranged derivatives of both the polymers and esteriflcation monomers, separately and jointly. Although the class of materials specifically contemplated in this instance is a comparatively small and narrow class of a broad genus, yet it is obviously impossible to present any adequate formula which would contemplate the present series in their complete ramification, except in a manner employed in the hereto appended claims.

Although the products herein contemplated vary so broadly in their characteristics, i. e., monomers through sub-resinous polymers, soluble products, water-emulsifiable oils or compounds, hydrotropic materials, fbalsams, sub-resinous ma terials, semi-resinous materials, and the like, yet there is always present the characteristic unitary hydrophile structure related back to the oxyalkylation, particularly the oxyethylation of the glycerol used as the raw material. As hereinafter indicated, in practising our process, the de-' mulsifier may be added to the emulsion at the ratio of 1 part in 10,000, one part in 20,000, 1 part in 30,000, or for that matter, 1 part in 40,000. In such ratios it well may be that one 'can not difierentiate between the solubility of a compound completely soluble in water in any ratio, and a semi-resinous product apparent-1y insoluble in, water in ratios by which ordinary lnsoluble materials are characterized. However, at such ratios the importance must reside in inter facial position and the ability to usurp, pr'w empt, or replace the interiacial position pr: ously occupied perhaps by the emulsifying 10 0. In any event, reveiwedin this light, the,

vious common property running through the entire series, notwithstanding variation in molecular size and physical make-up, is absolutely apparent. Such statement is an obvious over-simpliflcation of the rationale underlying demulsiiication, and does not even consider the resistance of an interracial fllm to crumbling, displacement, being forced into solution altered wetability and the like. As to a'midiflcationpolymers, for instance, where Z is the polyamino amide radical, see what is said subsequently.

COMPLETED PoLYmERIc DERIVATIVES INCLUDING HEAT-REARRAHGED COGENERS Example 1 COMPLETED POLYMERIC DERIvATIvEs Incummc HEAT-REARRANGID CooENERs Example 2 The same procedure is followed as in the preceding example, except that polymerization is continued, using either a somewhat longer reaction time, or it may be, a somewhat higher temperature, or both, so as to obtain a material having a molecular weight of approximately three to four times that oi the initial product.

COMPLETED POLYMERIC DEaIvA'rIvEs Incummo HEAT-RIARRANGID Cocnmms Example 3 The same procedure is followed as in Examples 1 and 2, preceding, except that one employs reactants derived' from more highly oxyethylated glycerol, or from oxyethylated ricinoleic acid instead of ricinoleic acid, or from an intermediate involving both such reactants as raw materials.

COMPLETED POLYMERIC DERIVATIVES INCLUDING HEAT-REARRANGED COGENERS Example 4 The same procedure is followed as in Examples 1 to 3, preceding, except that one polymerizes a mixture instead of a single monomer, for instance, a mixture 01. materials of the kind described in Completed monomeric derivative, Example 3, and in Completed monomeric derivative, Example 4, are mixed in molecular proportion and subjected to polymerization in the manner indicated in the previous examples.

It is understood, of course, that the polymerized product need not be obtained as a result of a two-step procedure. In other words, one need not convert the reactants I into the monomer and then subsequently convert the monomer into the polymer. The reactants may be converted through the monomer to the polymer in one step. Indeed, the formation of the monomer and polymerization may take place simultaneously. This is especially true if polymerization is conducted in the absence of a liquid such as xylene, as previously described, and if one uses a comparatively higher temperature, for instance, approximately 200 C. for polymerization. Thus, one pound mole of oxyethylated glycerol maleate of the kind described, ratio 1 to 15 up to 1 to 21, is mixed with two moles of ricinoleic acid and reacted for 20 hours at approximately 200", until the mass is homogeneous. It is stirred constantly during -reaction.- Polyfunctionality may reside in dehydration (etherization) of two hydroxyl groups attached to dissimilar molecules.

The fact that the polymerized and heat-rearranged products can be made in a single step, illustrates a phenomenon which sometimes occurs either in such instances where alcoholic bodies of the kind herein illustrated are contemplated as reactants, or where somewhat kindred alcoholic bodies are employed. The reactants may be mixed mechanically to give a homogeneou mixture, or if the reactants do not mix to give a homogeneous mixture, then early in the reaction stage, there is formed to a greater or lesser degree, suflicient monomeric materials so a that a homogeneous system is present. Subse quently, as reaction continues, the system may become heterogeneous and exist in two distinct phases, one being possibly .an oily body of moderate viscosity, and the other being a heavier material. which is sticky or sub-resinous in nature. In many instances it will be found that the thinner liquid material is a monomer and the more viscous or resinous material is a polymer, as previously described. Such product can be used for demulsification by adding a solvent which will mutually dissolve the two materials, or else. by separating the'two heterogeneous phases and employing each as it it were a separate product of reaction.

Conventional demulsitying agents employed in the treatment of oil field emulsions are used as such, or after dilution with any suitable solvent, such as water; petroleum hydrocarbons such as gasoline, kerosene, stove oil, a coal tar product such as benzene, toluene, xylene, tar acid oil, cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may be employed as diluents. Miscellaneous solvents,

such as pine-oil, carbon tetrachloride, sulfur dioxide extract obtained in the refining or petroleum, etc., may be employed as diluents. Similarly, the material or materials herein described, may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents. provided that such compounds are compatible. They will be compatible with the hydrophile type of solvent in all instances. Moreover, said material or materials may be used alone, or in admixture with other suitable well known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water-solubility. Sometimes they may be used in a form which exhibits relatively limited oil-solubility. However, since such reagents are sometimes used in a ratio of l to 10,000, or i to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed. This same fact is true in regard to the material or materials herein described, except that they are invariably water-soluble.

We desire to point out that the superiority of the reagent or demulsiiying agent contemplated in our herein described process for breaking V 2,344,Q80 I 'merals to 1; and 11' represents the numerals f petroleum emulsions, is based upon its ability to treat certain emulsions more advantageously and at a somewhat lower cost than is possible with other available demulsiflers, or conventional mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein described will find comparatively limited application, so far as the majority of oil field emulsions are concerned; but we have found that such a demulsifying agent has commercial value, as it will economically break or resolve oil field emulsions in a number of cases which cannot be treated as easily or at so low a cost with the demulsifying agents-heretofore available.

In practising our improved process for resolving petroleum emulsions of the water-in-oil type, a treating agent or demulsifying agent of the kind above described is brought into contact with or caused to act upon the emulsion to be treated, in ariy of the various ways, or by any of the various apparatus now generally used to resolve or the well at the bottom of the well, or at some point prior to their emergence. This particular type of application is decidedly feasible when the demulsifier-is used in connection with acidification of calcareous oil-bearing strata, especially. if

suspended in or dissolved in the acid employed for acidification. I

' As has been previously indicated, the sub-genus employed as an alcohol in the present instance is one of a series of alcoholic compoundswhich are contemplated in our co-pending applications Serial Nos. 447,152; 447,153; 447,154; 447,155; 447,156; 447,157; 447,158; 447,159; 447,160; 447,- 161; 447,162;'447,163;' 447,164; 447,165; 447,166; 447,167 and 447,168, all filed June 15, 1942,

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1.' A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged dc,- rivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

I in which R is the carboxyl-free radical of a polyl to 2. i

2. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of themonomers and aforementioned polymers, separately and jointly, and of the following formula: I

{(Cdln-OLuOOCRCOOZh cmaol ucnmon'l [(CJIflOL OOCRCOORr],

in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxy acid radical having at least 11 carbon atoms and not more than 36 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; n represents the numerals 2 to 4; n represents the numerals 3 to 10; :r' represents the numerals 0 to 2; y represents the numerals 0 to 2; and z represents the numerals 1 to 3.

3. A process for breaking petroleum emulsions of the 'water-in-oil type, characterized by sub- Jecting the emulsion to the action of a demulsifier comprising a member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivativels of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

lwzihmn'oocacooz canfion-iwzHioin fllt carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxy acid radical hav-' ing at least 11 carbon atoms and not more than 36 carbon atoms; Z is an acidic hydrogen atom equivalent including-the acidic hydrogen atom itself; n represents the numerals 3 to 10; a: represents the numerals 0 to 2; represents the. nu- ;nerals 0 to 2; and 2 represents the numerals 1 to 4. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the ar tion of a demulsifier comprising a polar member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heat-rearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

[(cna'imfl'oo01200021.r calm-ammon a]- in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a. water-insoluble hydroxy acid radical having at least 11 carbon atoms and not more than i 36 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; n represents the numerals 3 to 10;:1: represents the numerals 0 to 2; 11 represents the nuinoegals 0 to 2; and 2 represents the numerals 1 5. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subfier comprising a polar acidic member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heatrearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula:

[(cifiion oooncooz in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxy acid radical having at least 11 carbon atoms and not more than 36 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; 11' represents the numerals 3 to 10; a: represents the numerals to 2; 11 represents the numerals 0 to 2.;and 2 represents the numerals 1 to 3.

6. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjectins the emulsion to the action of a demulsifier comprising a polar acidic member of the class consisting of monomers, sub-resinous esterification polymers, and cogeneric sub-resinous heatrearranged derivatives of the monomers. and aforementioned polymers, separately and jointly, and of the following formula:

in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxy acid radical having at least 11 and not more than 18 carbon atoms; Z in' an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; it represents the numerals 3 to 10; :1: represents the numerals 0 to 2; 11 represents the numerals 0 to 2;

and 2 represents the numerals 1 to 3.

7. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifler comprising a polar acidic member of the class consisting of monomers, sub-resinous esteriflcation polymers, and cogeneric sub-resinous heatrearranged derivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula;

ciaiorucimowm,

[(mmon-oocncoom.

in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a water-insoluble hydroxy fatty acid radical having at least 11 and not more than 18 carbon atoms; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; 11' represents the numerals 3 to 10; 1: represents the numerals 0 to 2; 1! represents the numeral: 0 to 2; and 2 represents the numerals 1 to 3.

8. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifler comprising a polar acidic member of the class consisting of monomers. sub-resinous esteriflcation polymers, and cogeneric sub-resinous heatrearrangedderivatives of the monomers and aforementioned polymers, separately and jointly, and of the following formula: v

[(C2B4O)I\OOCRCOOZ] C:H:0:[(C:H10)-'H]| oimowoocao'ooall.

in which R is a carboxyl-free radical of a dibasic carboxy acid having not over 6 carbon atoms; R1 is a ricinoleic acid radical; Z is an acidic hydrogen atom equivalent including the acidic hydrogen atom itself; n represents the numerals 3 t 10; :0 represents the numerals'O to 2; 11 represents the rlumgrals 0 to 2; and 2 represents the numerals MELVIN DE GROOTE. BERNHARD KEISER. 

